Connector spring



CONNECTOR SPRING Filed April 7, 1958 INVENTOR 50 WA R0 M. A RM6 7R0/VG AITORNEYS United States Patent O CONNECTOR SPRING Edward M. Armstrong, West Carrollton, Ohio, assignor to Associated Spring Corporation, Bristol, Conn., a crporation 0f Delaware Applicatioir April 7, 1958, Serial N0. 726,962

1 Claim. (C1. 267-1) Tlnis invention relates broadly to springs and spring devices and, more particularly, to a =helical coil extension spring which is constructed and intended to be bent into substantially eircular forrn and to have its ends connected in order to be maintained in such annular form while in use. Such springs have a wide variety of uses, in a typical one of which the spring device plosely sur rounds and engages the brush of an electrical machine and is also connected to the eleetrieal lead to the brush, thereby providing an inexpensive, easily applied means for supplying electrieal energy to the brush. This invention has to do With springs of this type and while the springs provided 9by the invention have general utility, they will be particularly described in this speciiication springs for holding the brush of an electrical maehine.

It has been a particular object of this invention to provide a connector spring cf the described type comprising an elongated helical coil extension spring having new and improved means formed thereon for eonnecting the ends of the spring and for providing for the connection of an electrical lead to the spring.

The invention is described in the following specification and illustrated in the accompanying drawing, in wl1ieh:

Fig. 1 is a side elevational view of a spring device according to this invention before being formed into annular shape;

-Fig. 2 is a side elevational view of one end of the spring device of Fig. l, after being turned through 90 about the axis of the spring coil;

Fig. 3 shows the spring device of Figs. 1 and 2 formed into annular shape and having its ends connected;

Fig. 4 is side elevational view of a second embodir'nent cf the invention;

Fig. 5 shows the spring device of Fig. 4 formed into annular shape and having its ends conneeted;

Fig. 6 is a side elevational view cf one end of the spring device of Fig. 4, after being turned through 90 about the axis of the spring coil;

Fig. 7 is a side view of a spring device aecording to the invention as used to eonnect an electrical lead to a brush of an electrical rnaehine;

Fig. 8 is an enlarged top plan view of the parts shown in Fig. 7 and Fig. 9 is a view taken online 99 of Fig. 8.

The present invention provides, as a new article of manufacture, a helical coil extension spring w-hich is constructed in a new and improved manner Whereby it may be bent to annnlar forrn and, by having its ends connected, rbe maintained in that forrn, in which it is useful in a very great variety and number of ways as an annular, resilient eonnector device. While a spring forrned in aocordance with this invention is of general utility, it will be described in this specification, by way of illustration, as applied to a brush of an electrical machine in Order t0 support the brush and supply electricity to it.

A spring device formed in accordance With this invention is illustrated in Figs. 1 to 3 of the drawings and comprises a single length of wire forrned into an elongated helical eoil spring 2 -having uniformly spaced, preferably abutting, eonvolutions 4 throughout the greater part of its lengbh, thus forming an extension spring. At one end 6 at least one, preferably two, and possibly more, of the end eonvolutions 8 are separated frorn the main body of the spring and are connected thereto by a deformed.

and is then reversely bent through approximately Y as shown at 26, and is then continued to form a second straight part 28 which is of such length that it preferably extends approxirnately to the axis of the spring coil, as shown in Fig. 1. The parts 24, 26, 28 form a U- shaped hook at one end of the spring coil which may =be engaged with the separated coils 8 at the other end to hold the eoil in annular shape, as shown in Fig. 3. Tl1e axis of this hook, lying between the side legs 24, 28 and substantially parallel thereto, is substantially at right angles to the axis of the spring coil 2, as shown in Fig. 1 and in ehe ernbodiment of the invention diselosedin Figs. 1 to 3 the hook lies in a plane Whieh is substantially parallel to the axis of the spring :coil and tangential to the coil itself.

A second embodirnent of the invention is disclosed in Figs. 4, 5 and 6 of the drawings and is identical in C011- struction to the ernbodiment diselosed in Figs. 1, 2 and 3 with the exception only of the disposition of the end hook With respect to the spring eoil. In this form of the invention the end convolution 30 at one end of the spring eoil is continued tangentially and outwardly of the spring coil to forrn a straight part 32 Which is then reversely bent through approxirnately 180, as shown at 34, in a direction away r"rom the axis of the spring coil, and is then continued as a straight part 36. The parts 32, 34 and 36 form a U-shaped hook in a plane substantially at right angles to the axis of the spring eoil and lying outside the outer periphery of the rcoil, as shown in Fig. 5.

In the use of a device according to the invention the spring coil forrned as described above is bent into angular shape and the U-shaped hook at its one end is engaged with the separated coils 8 at its other end to hold the coil in the annular shape, after which it may be used as a retaining ring for a variety of purposes. For example, as shown in Figs. 7, 8 and 9, the annular spring rnay surronnd and tightly engage the one end of a brush 40 of an electrical machine (not shown). In order to efiect the connection of an electrical lead 42 to the spring 2, the lead is placed alongside and in engagernent with the two straight parts of the U-shaped hook and a malleable metal sleeve 44 is bent around the three parts to tightly engage and hold thern in contact with each other and prevent their separation.

The spring device provided by this invention may be easily and cheaply manufactured on known machines and rnay also be shaped to annular form on such maehines. "Ehe provision of a U-shaped hook at its one end and one er more separated convolutions at the other end permit quick and simple, but releasable, eonnection of the two ends of the spring.

While I have described and illustrated eertain embodiments of my invention it Will be apparent to those skilled 3 in the arts to Which it relates that other embodiments, as well as modifications of those disclosed, may be made and practised Withot departing in any way fro1n the spirit or scope of the invention, for the limits of which reference must be made t0 the appended claim.

What is claimed is:

As a new article 0f manufacture, a spring device comprising a helical coil extension spring the convolutions of which have uniform pitch throughout the greater part of the length of the coil, and at its one end having at least one convolution spaced axially outwardly fron1 the main body of the coil, the and convolution at the other end of the coil being extended tangentially outwardly from the coil and forrned into a U-shaped hook hooked end of the coil to connect t'ne ends of the coil and maintain the coil in annular shape, said hook lying in a plane at right angles to the axis of the coil and outside the periphery of the coiL References Cited in the file of this patent UNITED STATES PATENTS Coester et a1. Aug. 16, 1870 Saga] Mar. 12, 1940 OTHER REFERENCES Mechanical Springs, Their Engineering and Design, first edition. Copyright 1944, The William D. Gibson through the outwardly spaced convolutions at the other 15 Chicago, 111i110i5 Pages 42, 44 46 and 52. 

